指出下列自然现象或俗语中包含的物理知识： ①生活在沙漠中的仙_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题填空题

指出下列自然现象或俗语中包含的物理知识：

①生活在沙漠中的仙人掌针状的叶子______；

②墙内开花墙外香______；

③孤掌难鸣______．

答案

①生活在沙漠中的仙人掌针状的叶子是通过减小液体的表面积来减缓蒸发的；

②墙内开花墙外香说明了分子在永不停息的做无规则运动；

③孤掌难鸣说明了力是物体对物体的相互作用．

故答案为：①减少液体的表面积来减缓蒸发；②分子不停地做无规则运动；③力是物体对物体的相互作用．

计算题

（1）35-2.5x=5	（2）6×2.5+8x=23
（3）1.2x+1.3x-8= 4.6	（4）（2.5+x）×1.4=11.9

完形填空

It’s Saturday morning. Tony’s sitting at the kitchen table, 36  with a piece of bread. He’s not even   37 . Is he ill? No, but he does have a   38  .He has nothing to do becau se the Internet is down. When he   39  up this morning, Tony was feeling   40  . He jumped out of bed full of plans for the   41 ahead. It would be a weekend like any other---a great weekend. But that was before he turned on his   42  and found he was   43  to go online. Having no Internet changes everything.
Every weekend, Tony 44  goes online to email friends, reads the   45  to keep up with what’s happening in the world and   46  a few online chess games with his cousin Helen to finish the weekend off. The perfect weekend---online!
Just as Tony is wondering how he can possibly have a normal weekend   47  the Internet, his mum walks into the   48 . “Cheer up, Tony. Don’t   49  the Internet any more, OK?” Tony makes no   50  but sighs (叹气).“Go and play chess with Helen!” Tony’s mum  51  .
“Oh, yes! Helen   52  just around the corner. We can meet and play chess face   53  face for a change. Maybe this weekend won’t be so bad,” Tony   54  , as he walks to the phone. There is    55   without the Internet after all.

B．disappointed

A．living-room

C．think about